Biodiversity, once the preoccupation of scientists and greens, has become a mainstream concern. Liberal helpings of growth and technology are the best way of preserving it, says Emma Duncan

IF THE EVENTS of a single night can be said to have shaped the fate of life on Earth, it could be those that took place in Paragominas on November 23rd 2008. Paragominas is a municipality in the Brazilian Amazon two-thirds the size of Belgium. Its population of 100,000 is made up largely of migrants from the south of the country who were encouraged by the government to colonise the area and chop down the forest. The small town that is its capital has an air of the wild west about it. Men wear cowboy hats in the streets. Five years ago it was a rough place, its air full of sawdust and rumours that slave labour was used in the charcoal business fuelled by Amazonian timber.

Earlier that day, at the request of the mayor, Adnan Demachki, the federal environmental police had confiscated some lorries piled high with illegally cut logs (pictured below). The loggers were not happy. That night a few hundred of them entered the town, repossessed some of the trucks, set them and the office of the environmental police on fire and then tried to burn down the mayor’s office too. Paragominas was known to be the front line of the fight against deforestation, so the burning trucks were all over the nation’s television screens.

Mr Demachki, elected for his efficiency, not his political views, had come to believe that Paragominas was on the wrong side of history. He called a town meeting and held up two letters he had written. One apologised to the nation for the previous day’s events and committed Paragominas to stopping deforestation. The other announced his resignation. The townsfolk chose the first. The mayor stayed in his job, and Paragominas changed its ways.

The events in Paragominas have been repeated, in less dramatic ways, across much of the Brazilian Amazon. Deforestation has fallen steadily, from 28,000 sq km in 2004 to 5,000 in 2012. Whether this is a permanent victory or a temporary respite is not yet clear, but the fact that Brazil has succeeded in greatly reducing a seemingly unstoppable process of destruction raises hopes for the future of the rest of life on Earth.

The change has been a long time coming. Ever since man first picked up a spear, other species have suffered. Man wiped out most of the megafauna—the mammoths, the sabre-toothed tigers, the mastodons, the aurochs—that roamed the planet before he did. When he sailed the Pacific, he killed off half the bird species on its islands. As his technology improved, so his destructive power increased. When he learned how to exploit the Earth’s minerals and hydrocarbons, he started to multiply ever faster, leaving ever less room for the planet’s other species. He chopped down forests, poisoned rivers and killed large numbers of the biggest sea fish and marine mammals. Many believe that, as a result, a mass extinction comparable to those of prehistoric times may be under way.

In a sense, this orgy of destruction was natural. In the wild, different species compete for resources, and man proved a highly successful competitor. Religion sanctioned his ascendancy. The Bible granted mankind “dominion…over every creeping thing that creepeth over the earth”. If he stamped on a few of them, so be it.

But in recent times attitudes have changed. People have, by and large, come round to the view that wiping out other species is wrong. Part of the reason is pragmatic: as man has come to understand ecology better, he has realised that environmental destruction in pursuit of growth may be self-defeating. Rivers need to be healthy to provide people with clean water and fish; natural beauty fosters tourism; genes from other species provide the raw material for many drugs. But man also finds it troubling to think that as the only species able to marvel at the diversity of creation, he should be responsible for killing it off.

Putting Humpty back together again

The change in attitudes has had political consequences. In recent decades, first in the rich world and then increasingly elsewhere, laws to ban the killing of and trade in endangered creatures and to protect areas rich in biodiversity have been enacted. Governments are buying up important natural sites, restoring damaged ecosystems, setting up captive breeding programmes for critically endangered species and so on. Green NGOs and concerned individuals have also been helpful.

Endangered species have benefited from some of the concomitants of growth, too. Improved sanitation has made the planet healthier, as has regulation of pesticides. Cleaner air is better for biodiversity. As countries get richer, they tend to become more peaceful and better governed and their population growth slows down. Technological progress has improved life for other species, making conservation efforts more effective.

Although these successes can in part be credited to the environmentalist movement, greens tend not to boast of them for fear of damaging their cause. By walking the planet with a sandwich-board predicting impending doom, they have helped reduce the chances of an ecological calamity. If people believe catastrophe has receded, they may stop making an effort to avert it.

And they are right that the future for many species is by no means assured. Although things are improving in most of the rich world, in most of the emerging world—which is where the greatest number of species live—they are still deteriorating. Mass extinction remains a real danger.

Whether or not it actually comes about depends in part on what happens to the climate, which remains the subject of much guesswork. This newspaper has written about climate at length and this special report will not go over that ground again, except to say that if warming turns out to be at the upper end of the scale envisaged by the International Panel on Climate Change, the consequences for biodiversity—as well as for people—will be calamitous. If it remains at the lower end of the scale—as slower temperature increases over the past decade suggest it may—then most species will not be adversely affected.

Instead, this special report will focus on the relationship between humanity and the rest of the planet’s species in recent years. It will argue that thanks to a combination of environmental activism and economic growth the outlook for other species has improved, and that if growth continues, governments do more to regulate it and greens embrace technological progress, there is a decent chance of man undoing the damage he has done during his short and bloody stay on the planet.